URL to directly open an email from OWA stopped functioning on smartphones

Question

We use Graph API to obtain a URL (weblink) for a message inside an Outlook mailbox.

The URL we retrieve is of the form:

"webLink": "https://outlook.office365.com/owa/?ItemID=AAMkAG...&exvsurl=1&viewmodel=ReadMessageItem"

We then launch this URL with a web browser. The browser displays the message (after the user has been authenticated), and the user can take any action, like reading the attachments, replying, etc.

This is when opening the weblink from a PC. If you try the same from a smartphone, the message opens up, but no actions function. Attachments can't be opened; Reply or Forward present just a blank screen.

Behavior is the same on any phone (Android or iOS) and with any browser.

If you change the phone browser to "Request desktop site," the message functions properly; however, the layout is horrible.

The same URL used to work fine on the phones until about April or May.

How can we overcome this issue? It is critical for us and many of our customers.

Answer 1

This is to add that further experimentation has revealed that non-MS Office attachments will work and allow you to download them. MS Office and PDF types that would be handled natively by OWA by spawning another page will not work.

Also, as said earlier, the Reply, Reply All, and Forward actions (which require spawning another page) do not work; however, the Mark as Unread and Delete actions work fine.